Apparatus for coating and treating sheet material



A. Y. PEARL 1,329,153

G SHEET MATERIAL APPARATUS FOR COATING AND TREATIN Original Filed July 1926 6 Sheets-Sheet 1 A. Y. PEARL 1,829,153

a sum m'rimum Oct. 27, 1931.

APPARATUS FOR COATING AND TREAIIN n l Filed y 1926 6 Sheets-Sheet 2 a M! W W b m 71M Md SHEET MATERIAL Oct. 27, 1931. A Y. PEARL APPARATUS FOR COATING AND TREATING Original Filed July 1926 6 Sheets-Sheet 2 A. Y. PEARL 1,329,153

SHEET MATERIAL Oct. 27, 1931.

APPARATUS FOR CUATING AND TREATING Original Filed July 2, 1926 6 Sheets-Sheet 3 MATERIAL A. Y. PEARL A Oct. 27, 1931.

APPARATUS FOR COATING AND TREATING SHEET Original File ly 1926 6 Sheets-Sheet 4 j 3 W m. a

Oct. 27, 1931. PEARL 1,829,153

APPARATUS FOR COATING AND TREATING SHEET MATERIAL Griginal Fil y 1926 6 Sheets-Sheet 5 z W/ AV A. Y. PEARL Oct. 27, 1931.

APPARATUS FOR COATING AND TREATING SHEET MATERIAL Original Filed July 1, 1926 6 Sheets-Sheet 6 of my application common solvent, together,

Patented Oct. 27, 1931 UNITED STATES PATENT OFEICE v 1 AZARIAIIIY. PEARL, OF WmDSOB, VERMONT, ASSIGNOB TO IIJABOR-ATOIRES SEVIGNE- PEARL, 0! WINDSOR, VERMONT, A CORPORATION OF VERMONT APPARATUS FOR COATING AND TREATING SHEET MATERIAL Original application filed July 2, 1926, Serial No. 120,198. Divided and this application filed October 8 1,

1928. Serial No. 818,143.

This application relates to apparatus for been expelled, giving light and shadow efproducing coatings on continuous sheet mafects correspon 'ng to the light and shadow terial such as paper, and constitutes a dlVlSlOIlefi'ects of crystals. By varying the type of Serial No. 120,196, filed crystal employed, the concentration of crys- July 2, 1926. tal in solution, the conditions of crystallize- VVhile' not limited thereto, the apparatus tion, and the coloring agent the appearance the present invention is especially serviceof the product may be varied.

coating material is one comcoating or film such as hereinbefore deprisingavolatile solvent, and the coated sheet scribed not only is highly attractive, but is waterproof, greaseproof, flexible, and possesses other characteristics incident to the makln ornamental coatings such as deusual nitrocellulose coatin or film. The scribe in my application for patent hereincoloring of the coating or fi lm, moreover, is bef ore identified. herein described, 'not attracted by water, owing to the fact that nitrocellulose and a suitable crystallizable the color is retained in the water-impervious compound sublimable or vaporizable below nitrocellulose. Hence the colored material the decomposition temperature of nitrocellu-. may be washed or cleaned without deleterious lose, are dissolved in proper proportion in a efi'ect. It may be applied tp sheet material,

if desired, with'a e. paper, to produce a hi hi agent or dye. The solution is then product suitable for use as a in the form of a thin coating to a suitcandy box manufacture, or for a la base, preferably at a temperature suflitive uses. a 1 cientl .low to prevent rapid evaporation of e present invention, as already stated, is the so vent. Upon evaporation of the'solvent, concerned with for forming such instance, it may be used to advantage when color-1n paper, for

other decora-' pound crystallizes within'and throughout the entire coating. The product is then treated. paper, and the crystals subsequently formed to remove the crystals', for example it being therein are liberated to produce the crystal heated or cured to about the subliming or line intaglio. The machine of the present vaporizing temperat r of the crystals .invention, therefore, comprises a coating detrapped therewithm, so that they are released an E leavmg behnld m mtagho m predetermined thickness over thepaper. The h coatmg h natur design or nfi deviceincludes a box having a series of gates A thus made although through which the solution flows fil l of mtroce pmsents a remarkably tinuous layer overthe paperwhich progresses at predetermined rate thereunder. The device further includes an adjustable doctor which distributes the coating material evenly over the paper.

The coated light-reflective or lustrous. e c'rysta line appearance may be attributed to the fact that the coating reflects and refracts light in a manner similar to the crystals which have lization. After crystallization, the paper is cured in a room at a temperature sufiiciently high to liberate the crystals, but below the attractive vice which applies and distributes a layerof temperature of decomposition of the nitrocelfound to be monobrom-camphor, which forms lulose. long, radiatin monoclinic' c stals, sublim- With these and other objects in view, the ing at 76 C. ther crystalliza le compounds invention consists in certain novel features may be employed, however, such as salicylic of construction, combinations, and arrangeacid, benzoic acid, resorcinol, borneol, terments of parts as will be more fully herein pene hydrate, menthol and thymol. Certain after describe in conjunction with the 210- of these compounds which possess certain companying drawings, wherein features of advantage over monobrom-cam- Figure 1 represents diagrammatically a hor are less desirable in other respects.

, side view of the cold room end of a machine hus, salicylicacid is an odorless, relatively for continuously coating paper or similar cheap compound, but its crystals are not so sheet material with the composition of this large or well defined as those of monobrominvention. camphor. Certain other compounds, such as Figure 1a similarly represents a side view menthol and thymol, would be too expensive of the hot room end of the machine and ordinaril for commercial use. 8 shows the paper, as it passes into the hot The so vent may be an suitable volatile -room from the cold room. solvent which efiects a so ution of both the Figures 2 and 2a, respectively, represent nitrocellulose and the crystallizable complan views of the cold and hot rooms. pound. A common solvent, may, for exam- Figure 3 illustrates an end view of the cold ple, be strai ht. acetone, an alcohol-ether room, showing auxiliary apparatus and pipmixture, amy acetate, butyl alcohol, a mixing for the coating device. ,ture of benzol and ethyl acetate, or other soligure 4 is a side view of the device. vents or mixture of solvents. A relatively Figure 5 is a similar view,,showing the cheap solvent, known as solvent L in the 25 device mounted on the machine. trade, has been successfully utilized. This Figure 6 represents a plan view of the solvent contains approximately 40% to 50% some methyl acetone, 20% to 30% methyl acetate, Figures 7 and 8 are sections on the lines and 30% methyl alcohol, and possesses the 7--7 and 8 -8, respectively, of Figure 4. advantage of being highl volatile, boiling 3o Figure 9 is a section on the line 9--9 of at 54 to 57 C. A suitab e dye or lake may Fi ure 8. be added to the solution. The coating or film igures 10 and 11 are sections on the lines may, however, be colored after it has been 10--10 and 11-11, respectively, of Figure 4. formed. I may, for example, add Victoria Figures 12 and 13 are sectionson the lines blue to the solution, or a soluble dye of any 35 12-l2 and 13-13 of Figure 10. other desired color. Figures 14 and 15 are sections on the line As a s ecific example of procedure which 14-14 of Figure 11, showing the coating demay be ollowed in producing the solution, vice in operative and inoperative positions, the following will sufiice. About 14 pounds res ectively. of nitrocotton and 20 pounds of monobromig. 16 shows in perspective a fragment camphor are mixed, with stirring, into about of coated palpe 25 gallons of solvent L until a complete solu- Fig. 17 i ustrates in enlarged plan view tion of the material has been efiected. The a fragment of paper. resultin solution has a consistency or vis- Fig. ,18 'is a highly magnified section eosity 0 about that of honey. The solution 45 through thepaper. is applied in the form of a thin coating to In making ornamental coatings such as the base and the solvent is then allowed to described, the nitrocellulose or lllifll'OCOlltOn evaporate at relatively low temperature,

employed as a raw material may be of low whereupon a setting of the coating and a nitration, similar to thatpmploged 1n the crystallization of the brom-camphor takes so manufacture of artificial silk, an may conla The roduct is th n h t d t t tam, for exam 16, 117 ni r g erature. su cient'ly high to liberate the when dlssolv a the $9053 of the result- Erompamphor crystals, but below the teming solution depends upon t e character of t f d c iti f h the nitrocotton. Inasmuch as evaporation l 55 of solvent takes D l&ce m r uickly f a The cured coating, as shown in Fi re 16, solution of low 'flsoo l y, n a g is continuous and is composed of radiating,

nitrocellufihn producing better sheen produced, t crystal-simulating clusters 0 of various sizes,

nitrocotton is pr fer ly ppro m y which lie adjacent to one another and are four-secon lacquer cotton. 1f nitrocotton bounded by well-defined lines 1. Each radiproducing solutions of high viscosity are emating crystal-simulating cluster 0 may have played, a, padded crystalline appearance an appearance s'milar to that of the grain results. 1 of a transverse section throu h wood, and

One of the most satisfactory crystallizable may be composed of rings d of rogressive'ly compounds which possesses the desired physilarger diameters, continuing fii'om the m1- cal and chemical characteristics has been clone 0' of the cluster to its boundary, and 1 0 radial needles extending from "ring to ring.

The crystalline eiiect may be varied by varying the concentration of monobromcamphor of nitrocotton in the solution. Thus, if the concentration of monobromcamphor in the solution prepared as hereinbefore described is raised to, say, 26 to 30 pounds, only radial lines will be present in each cluster and the rin s will disappear entirely. If a solution l iaving a somewhat lower concentration of monobrom-camphor, say 16 ounds, is employed, a combination efl'ect oi radial lines at the nucleus of the cluster and radial lines and rings at the boundary of the cluster will be produced. If, on the other hand, the concentration of nitrocellulose in solution is raised to about 16 to 17 pounds and the concentration of monobrom-camphor is maintained at 20 pounds, the ring effect will be enhanced and the well-defined lines between the cluster will become indistinct or disappear. In other words, a decrease in the relative concentration of cotton enhances the radial effect;

whereas an increase enhances the ring effect. This henomenon may be imputed to the fact that with a relative increase of cotton the viscosity of the solution is raised, and consequentl crystallization is sufiiciently resisted to e ect an intermittent crystallization, resulting in discontinuous crystals and producing a wood-ring efi'ect. On the other hand, when the viscosity of solution is low, a continuous crystallization producing an uninterrupted radial needle efi'ect takes place. When a colored solution is employed, the color at the nucleus of each crystal cluster is somewhat darker, and is adually and increasingly lighter toward its boundary, thus imparting a pleasingly variegated color effect to he coating.

Referring to Figure 1 of the drawings, a roll of paper S is shown at 1, mounted for unwinding on spaced supports 2, 2' within a cold room 10. The paper is unwound from the roll and is successively brought over and under a pair of guide and tension rolls 3 and 4, respectively, rotatably mounted in the framework of the machine, and thence backwardly and over a large rotary roll 5, above which the coatin device is supported. To permit a film 0% uniform thickness to be aid on the paper, the roll 5 is ,highly finished, so that the paper lies perfectly flat from side to side on its surface.

Inasmuch as the solution is dillicult to handle with pum due to the evaporation of the solventan the consequent setting of the dissolved material, this machine to deliver the solution to the coating device with compressed air. As

shown, compressed air from a compressor 31 is forced through a pipe 32 above the solution level maintaine 1n the closed supply tank 30, into which the prepared solution is provision is made in and 53, respectively,

delivered from a pre aration tank (not shown). The solution is driven up through a ipe 33 into a manifold 34. A series of va ved pi es 35 communicate with the manifold, eac pipe leading into a container 36 serving for solutions of difl'erent colors, located above the coating device.

Each tank 36 may be equipped rwith'a vent 36a and also a gauge 362), for ascertaining the height of solution therein. The solution is allowed to flow by gravity down through a pipe 37 from each tank and through a tube 48 into the coatin device. The level of the solution in the levice is maintained at a constant head by a valved overflow pipe 39, which discharges the overflow into the tank 30. *The pipe line 37 is provided with a shut-oil valve 38, which is closed when the device is to be drained, so that the solution may flow from the device through a pipe 40, valved as at 41, into the tank 30.

With this solution-feeding system, when one color is employed, the valves of the pipes 35 for the other colors are entirely shut off. This eliminates the necessi y of cleaning of all the pipes 35, which are of considerable length, and all the containers 36 when a change of color is to be made. Cleaning may be effected by passing a solvent through the system. The cleaning solvent may be reutilized in making up a fresh solution of the particular color which ithas acquired during its cleaning action. The pipe lines are preferably constructed with cross fittings at all turns, so that they may be supplied with removable plugs at their open end, the plugs being removed and the pipes cleaned with brushes if a setting of the nitrocellulose takes place within the The coating device comprises a closed box designated as a whole as 45, for containing a supply of the solution, and having an outlet 0 at its bottom, through which the solution is discharged in a thin layer of substantially uniform, predetermined thickness. By this means, unnecessar loss of the solvent by evaporation, and a so danger from fire, such as would occur if the solution were sprayed on by the use of compressed air, is in large measure averted. The box is hingedly supported at one end byspaced portions 47, 47a through which the supply tube 48, which serves as a pintle, passes. The tube is extemally finished so that the device may be easily swung thereabout, and is provided at the central knuckle 47a with a plug 49 having solution inlet and outlet ports 50 and 51, respectively, formed through its ends and sides and which communicate through these ends with the interior of the tube and through its sides with openings through the side of the tube. Spaced inlet and outlet apertures 52 are formed through the bottom of the box at the central sleeve pertion 47a, permittin introduction of the solution 'into the device through the'port 50 and draining of the solution from the box through the port 51. When the box is in horizontal operative position, shown in Figure 14, the inlet aperture.52 registers with the port 50, as shown, allowing the solution to pass into the box. The rate of flow into the box may be regulated by a valve 55 at the aperture 52. The valve, as shown, is on the lower end of a rod 56 threaded through the top of the box. By turning the portion 57 of the rod projecting above the box top, the valve may be raised or lowered so that the rate of How through the aperture and past the valve into the box maybe accurately governed. The solution flows through a tubular wire strainer 91, which extends from the bottom of the box to its top, so that any solid impurities contained therein are caught and retained on the wire. When draining of the device is desired, it is swung back 90 about its supply tube 48, by means of a handle .58 fixed to one of its sides, to its inoperative, vertical position shown in dotted lines in Figure 5 and in Figure 15. In so doing, the inlet'aperture 52 through the box bottom is moved out of registry with the inlet port 50, and the outlet aperture 53 is alined with the outlet port 51, permitting the solution to drain by gravity from the box into the supply tank 30. To allow com lete draining to be effected, the bottom 0 the box is preferably sloped or inclined at 59, 59 at its sides. The bottom of the box exteriorly is preferably provided with a trough 92 extending transversely thereof, so tha when the box is swung to its inoperative vertical position, the trough catches any drip flowing down the outside of the bottom, and thus prevents such drip from reaching the roll 5 or paper thereon. This drip may be carried away by a pipe 92a communicating with the bottom of the trough. Preferably, also, a sight gauge g is provided at the back end of the box to permit the operator to ascertain the height of the solution in the box at any time when the box is in o erative position. For maintaining atmosp er1c pressure within the box, a vent pipe 1; isshown as extending from the back end of the box forwardly across its top to a suiiicient distance, so that the box may be swung to its inoperative vertical position without escape of the solution at the open end of the pipe.

Provision is made to regulate the flow of solution from the box to produce a layer of predetermined thickness and width on-the paper, preferably by a micrometer adjustment. To this end, secured internally-to cpposite sides of the box, are a pair of blocks 60, 60, which are channeled or grooved to receive the gates 61, 62, 73. The gates 61 and 62 may be relatively adjusted for regulating the rate of flow of the solution. As shown best in asser s Figures10 and 13, the gate 61 is stationary. being fixed against movement to the bottom of the box. .At the lower edge portion, it is provided with a series of openings or slots 61a, s seed at regular intervals from one side 0 the box to the other. The gate 62 is somewhat shorter than the gate 61, approximatelv by the length of a slot 61a, and is movable lengthwise, and it is maintained against the gate 61 and guided in its movement by an angle iron 63 secured to the bottom of the box. The gate 62 is also provided at its lower edge portion with a series of slots 62a spaced at regular intervals. These slots are registerable in greater or less degree with the slots 61a by lengthwise movement of the gate 62. Movement may be imparted thereto by axial movement of a shaft 66 passing throu h and threaded in a side of the box. The shaft is provided at its inner end with a disc 64 fixed thereto, engaging within a slot 65 cut in the gate 62. The shaft is threaded through one end 67 of a semi-cylindrical casing 75, fixed externally to the side of the box, and passes through and is journaled at its enlarged, unthreaded outer portion 66a in the other end 68 of the casing. Fixed to the unthreaded end 66a is a knob or dial 69, rotatable b hand and having graduations marked t ereon. A pointer fixed to the end 68 of the casing cooperates with the graduations to indicate the angular position of the dial at any time. Fixed on the shaft between the ends 67 and 68 of the casing, is a knife-edged disc 71 in reading relation to a scale arranged parallel to the shaft and located at the upper edge of the casing. This disc travels axially with the rotation of the shaft by the dial 69, and indicates the axial position of the shaft and thus the amount of i registry between the gate slots, accurate fractional parts of the scale units being ascertainable by the points 70 and the dial graduations. Thus by providing the shaft with 40 threads or inch and the dial 69 with 25 graduations, it will be seen that by turning the dial one graduation the disc 71 and similarly the gate 62 moved thereby have been caused to travel 1/1000 of an inch. Consequently, very accurate adjustments of the rate of flow of the solution may be made. The maximum amount of registry of the gate slots and the'maximum rate of flow occurs when the disc is moved to the end 67 of the casing, these values diminishing as it is moved toward the end 68.

The solution flows through the portions of the slots brought intoreglstry, in a series of uniform streams, over .the bottom of the box, which is extended beyond the gates, the streams diverging or spreading thereon and joining with one another to form a continuer. The thickness of the layer will depen of course, upon the size of the several streams, which may be varied by varying flow of the film. thereunder.

azarus the amount of registry between the gate slots.

This layer flows under the lower edge of the third gate 73 extending from one side of the box to the other. Provision is made to obstruct the fiow-under the gate 73 at both ends thereof to produce a film of predetermined width. As shown, a slot 730 is formed inwardly of each of the ends of the gate 73 to define 0 positely extendin tongue portions 730, a out which fabric 5 or other suitable material of the desired width and thickness is wound in successive convolutions. The fabric at the bottom edge of the gate rests on the bottom of the box and prevents The lower edge portion'of the gate between the obstructed ends smooths out any marked unevenness in the continuous layer as itpasses thereunder. The gate 7 3 is vertically movable in its channels in the blocks 60 and is provided with lifting knobs 73b, threaded into its upper edge portion, so that when the top of the box is removed, the knobs may be grasped to lift the gate out of the box for'cleaning or for the renewal of the fabric.

The solution flows as a continuous layer of predetermined thickness and width through the slot 0 in the box bottom beyond the gate 73 on to thepaper as it passes at a predeter mined rate over the large roll 5. To distribute the solution properly on the paper, as

well as to smooth out any surfaceyirregularities therein, the device is provided with a doctor 76 (Figures 4 and 7) provided with a lower knife edge 760. To prevent the solution from streamin out laterally of the ends of the openin obstructions, such as small rolls 1', f drmed from fabric, may be placed thereat on the rolls 5 between the lower edge of the doctor and the edge of the box bottom, the rolls wiping along the surface of the roll 5% it is rotated, and being held in position by adjacent parts of the box and the roll face.

The doctorfis adjustable to the desired degree above the paper, being guided within ways in the blocks 60, 60 for such adjustment.

It 1s supported at both ends at its upper edge portion by a pair of vertical shafts 77 and 77a, each journaled for rotation in a bearin 78 afforded by an upstanding bracket 80 fixe Each shaft is threaded through a In 79 provided at the corresponding end of te doctor, so that rotationof the shafts imparts upward or downward movement of the doctor. To effect such rotation, the shafts 77, 7 7a are respectively provided with worm gears 81, 81a loosely mounted thereon and resting on the bearings 78. To prevent translatory motion of the shafts 77, 77a, a collar 77b is fixedthe bearing 78.

to each at the'lowe'r end of Fixed to each shaft and bearing on its re spective worm gear is a khob 82, which is normally clamped down to its gear 81 by a thumb screw 83 threaded into its gear and turned down so that the under face of its head engages the upper face of the knob 82, whereby when its gear is rotated the roll 82 and its shaft are rotated therewith. Simultaneous rotation of the gears 81, 81a and a corresponding raising or lowering of the doctor may be efiected by a worm shaft 84, provided with the worms 85, a meshing respectively with the worm gears 81, 81a. Either end of the doctor may be adjusted independently by releasing the screw 83 at one end so that the shaft at that end may be rotated independently of the shaft at the other end. Rotation of the shaft 84 ma be effected by turnin a graduated knob 86 xed to one end thereo? and with the graduations of which a suitable pointer 860 cooperates. The doctor thus may be accurately adjusted at either or both ends by thousandths of an inch, so that its knife edge may be'caused properl to distribute and smooth down the layer 0 solution flowed on to the paper.

The box is supported at its outlet end at each side on the roll 5 beyond the edges of the paper by a roller 87 ,journaled for rotation on the corresponding end of a shaft 88 extending from one side of the box to the other. The shaft 88 is iixed at each end to the other end of a lever arm 89pivotally secured at its opposite end as at 890. to a slde of the box.

he box is adjustable up and down relative ,to its lever arms 89, to regulate the clearance for papers of 'diflerent thicknesses passing under the box. To this end, oh each side of the box, there is provided an adjusting screw 90 threaded through a lug 91 projecting from the side of the box. The lower end of the adjusting screw bears against the arm 89 and may be turned to raise or lower the box slightly as may be desired. The device thus deposits a layer of the coatmg solution of substantially uniform and predetermined thickness and width over the upper surface of the paper. posited is very thin, so that the crystals subsequently formed lie in a sin le layer therein and may be driven off. I a film of too great thickness is applied, a padding or piling up of the crystals results, and the expulsion of the crystals is rendered difiicult and a less pronounced crystalline appearance is produced in the roduct. To yield an optimum crystalline e ect, the film as applied preferabl is approximately .005 to .008 inch in t ickness. When cured and set the film shrinks to a thickness of about .001 inch. A control of the thickness of film to thousandths of, an inch may be elfected readily by the coatin device constructed as hereinbefore described.

The coated paper passes substantially hori- The coating de closely adjacent to the surface of water maintained in tanks 7. The uncoated face of the.

warmed in the surface.

paper is thus subjected to moist air, which serves to counterbalance the tendency of the paper to curl owing to the solvent in the coatmg on its upper face. If desired, the rolls 12 may be arranged on a slight camber to cause a distortion ofthe crystals from natural formation. Various crystalline appearances are possible by varying the arrangement of the rolls. The roll 5 and the table rolls 12 may be driven at the same rate of speed by an suitable means to aid in effecting a propu sion of the paper thereover and the unwinding of the paper from the roll 1. As shown, the roll 5 is geared at one end 96, through an idle gear 96a to a gear not shown) fixed to a driving shaft 97 he shaft 97 is provided with a pulley 97a, which is belted to a driving pulley 98a of a speed reduction unit 98 for a motor 99. The first table roll 12 adjacent to the roll ,5 is provided with a driving alloy 100 at one end, which is belted to a pu ley 101 on the driving shaft 97 The first roll is also belted to a pulley 101 on the end of the second roll 12, to drive it at the same rate of speed: The second roll is provided with a sprocket at one end thereof, over which a chain 102 passes forwardly to drive similar sprockets fixed to the corresponding ends of the remainin table rolls 12, at the same rate of'spee The chain passes downwardly from the last roll 12 over the idle sprocket 103, thence backwardly through a tube or pipe 105, which serves as a guard, over a similar idle sprocket 104, and finally upwardly over the sprocket on the first roll.

The aper may be maintained at a substantially xed and relatively low temperature during the crystallization which takes place in the coating, to prevent rapid evaporation of solvent. If rapid evaporation of solvent were permitted, large crystals would not be given suflicient time to form, small crystals being produced. The freshly coated aper is then caused to pass through the col room. If the atmosphere of'the cold room is maintained at relatively low temperature, say, about 50 to 60 F., the formation of relatively large crystal groups is favored. The atmosphere of the room may be maintained at the desiredtemperature by circulating a suitable refrigarant through pipes 120 positioned alongside the walls of the room adjacent to the machine. The refrigerant pipes 120 may be compressed and condensed in a compressor shown at 130 and returned and ex ended in the pipes. To

crystallization the coating is prefpromote erably slightly disturbed from its state of quiescence by air blown gently against its This produces a gentle excitation in the coating. so that crystal inoculation is initiated. The crystal-clusters grow from a nucleus to the size of a pea in a l0 foot travel, the paper progressing at a rate of about 10 to through into the curing 20 feet per-minute. Crystallization into clusters of considerable size is effected in a 30- foot travel at this s 'eed. As shown, the room air is delivere against the coating from nozzles 13 and 14, which communicate through a common conduit 15 with a fan blower 16 driven as bya motor 17.

The sheet is again pro elled or driven and further aided in unwin ing from theroll 1 by passage over and in contact ,with an endless driving apron or belt 160, made of rubber fabric, or the like. The apron is perforated and passes over a suction box 170 maintained under suction by an exhaust fan 18 communicating with the box through a conduit 19. The paper is drawn against the apron by the suction, so that as the apron is driven the paper is carried along therewith by friction. The apron may be driven as by rotation of eithera pair of rolls 119, 120, about which it passes. As shown, the roll 119 is rotated a worm gear 21, fixed toone of its ends by a worm 20a on the end of a worm shaft 20. The shaft 20 may be driven by a pulley 121, over which a driving belt 22 from a motor pulley 23 passes. A drive such as described propels the paper with little vibration, so that a state of quiescence which favors the growth of large crystals may be preserved during crystallization. The apron is driven at a rate of speed somewhat higher than that at which the roll 5' and the table rolls 12 are driven, to produce a, steady tension on the paper, smoothing it and preventing wrinkling or bunching of the paper at the apron. In practical operation in one commercial .machine the paper travels about 120 feet in the cool room, during which time coating fected. The paper is 30 inches in width, and the propelling stretch of the apron is 5 feet long. These dimensions, it should be understood, are of an actual installation and are given by the way of example only After crystallization, the paper is passed or hot room 11 through a slot in a partitionS the cold and hot rooms where the crystals are released from the coating by heat. As shown in Figure 1a the paper is festooned or looped as it passes into the hot or curing room, the

looping mechanism herein conyentionally' shown being a Stubbs looper. 3 Each loop is supported by a roll or rod 25, and is slowly carried along in reversely extending lanes or rows, through the curing room,- the cured paper product roIl-Me- During the curing operation, the coating is exposed to the atmosphere of the room, which 15 maintained at a temperature of about 100 to 120 F., thus eifecting an expulsion of the monobrom-camphor crystals by volatilization or sublimation thereof. Furthermore, an solvent wh ch may not have evaporated uring crystallization is ex- (Figures 1a and 2a) between finally being wound up on a polled. During operation, the interior wall surfaces of the curing room become coated with monobrom-camphor crystals, which may be recovered and re-em loyed in making up the coating solution. irculation of air in the curing room may be maintained by exhausting the air therefrom through a head 27 communicating through a conduit 28, with an exhaust or suction fan 29. The air exhausted from the room may be treated for the recovery of solvent and crystallizing compound contained therein.

Traces of the crystallizing material may remain in the coating after treatment in the curing room, this being noticeable by the camp or odor which the paper possesses, but this gradually disappears as the pa er ages and curing becomes completed, W ere the paper is employed as wall paper or for decoratively lining trunks or drawers, however, a residual amount of monobrom-camphor may advantageously be allowed to remain therein,

. pinkcolored back crystals only are the surface so that it may and insects.

A complete curing of the coating may be accelerated by treating the film with a monobrom-camphor solvent which does not attack the nitrocellulose. Thus if treated with carbon tetrachloride prior to curing, the carbon tetrachloride dissolves a portion of the crystals and is volatilized therewith during the curing operation assisting in eifecting a complete curing of the film. If desired, the paper to which the coating is applied olfer a. contrasting serve to; repel certain bacteria mi be colored to backgroun to thb coating. For example, a round and a colorless coating give the one eus of each crystal-simulating cluster :1 distinct pink tint, variable towards its boundaries.

If the base is coated by spraying the solution thereon, the volatile solvent is rapidly evapdrated and ample time for large crystal formation is not allowed. In such case, small reduced. Where a base such as leather, ru ber, bakelite, wood, etc, is to be coated, the base may be dipped into a solution of suitable viscosity, and then allowed to drain until a coating of the proper thickness remains. Subsequent crystallization and curing bring out its crystalline ap pearance. I

When such material as paper, cloth, leather, or the like, is coated, the solution penetrates portion thereof, so that the coatmg becomes partially embedded therein. As shown in Figure 18, the coating f is partially embedded in the surface portion of the paperb. For coating such material as leather, a solution of monobroIn-camphor in amyl acetate may be advantageous, due to the fact that larger crystal-simulating clusters. having more sheen areproduced. This is due to the fact that-crystallization from amyl acetate the coating is requires a longer time than from solvent-L, due to the lower volatility of the amyl acetate.

When the coating is deposited on a smooth, impermeable base, such as glass or metal, it may be stripped off in a continuous, coherent condition. The stripping may be facilitated b first immersing the base in hot water.

his reduces unequal expansion of the base and t e coating and permits the coating to be stripped off in a continuous, coherent film with relative ease. The stripped film, if desired, may then be united with a suitable base by an adhesive. It may, for example, be applied to a base such as glass, and serve as a ackground for printing.

In lieu of nitrocellulose, I may employ any equivalent thereof, e. g., a um or wax which will form a film and Whic is soluble in the same solvent in which the'crystal-forming substance is dissolved. A simi ar effect may be produced as with nitrocellulose, though it may lack something of the beautiful silky or satiny appearance incident to the use of nitrocellulose.

Having thus described this invention, it should be obvious that it is capable of various changes and modifications without departing from its spirit or scope as defined by the appended claims.

I claim:

1. A machine of the class described, comprising a roll over which sheet material passes, means for applying a coating of substantially uniform, predetermined thickness on said material while supported on said roll, a plurality of rolls for supporting the sheet during the setting otthecoating, over which said material passesfisubstantiallyhorizontally from said first-mentioned roll, a horizontal suction apron over ,yvhich said material passes, and means for driving said suction apron p 2. In combination a cold and a hot room, in which continuous sheet material is suc cessively treated, means for supporting the sheet material in ,fiat, unwrinkled condition in said cold room, means for,applying a coating of substantially uniform, predetermined thickness to said sheet while thus supported, means in said cold room for supportmg the sheet during the setting of the coating, means for looping or festooning said sheet in said hot room, and means for propellipg said sheet through said rooms.

3. In combination a cold and a hot room, in which continuous sheet material is successively treated, means for supporting the sheet material in flat, unwrinkled condition in said cold room. means for applying a coating of substantially uniform, predetermined thickness to said sheet while thus supported, means in said cold room for supporting the sheet during the setting of the coating, means said hot room, means for exhausting the air less degree with sai therefrom, and means for propelling said sheet through said rooms.

'4. A coating device comprising a box for containing liquid coatin material, a fixed, vertical gate extending rom one side of the box to the other and having a plurality of slots therein, and an adjacent, movable, vertical gate having slots registerable to greater or less degree with the slots of said fixed gate to regulate the rate of flow of material through said gates.

5. A coating device comprising a box for containing liquid coating material, a fixed, vertical gate extending from one side of the box to the other and having a plurality of slots therein, an adjacent, movable, vertical gate having slots re 'sterable to greater or less degree with sai fixed gate to regulate the rate of flow of material through said gates, and means for moving said movable gate. l

6. A coating device comprising a box for containing liquid coating material, a fixed, vertical gate extendin from one side of the box to the other and aving a lurality of slots therein, an adjacent, movable, vertical gate having slots re "sterable to greater or fixed gate to regulate the rate of flow of material through said gates, and micrometer adjusting means for moving said movable gate.

7. A coating device comprisin a 'box for containing liquid coating material, a fixed gate extending from one side of the box to the other, and having a pluralitdy of slots at regular intervals therein, an a jacent movable gate having slots registerable to greater or less de ree with the slots insaid fixed gate, a rol engaging said movable gate, a shaft to the inner end of which said roll is fixed threaded through a side of the box, and a. knob at the outer end of said shaft by which said shaft may be rotated to efl'ect a movement of the movable gate.

8. A coating device comprising a box for containing liquid coating material, afixed gate extending from one side of thebox to the other, having a plurality of slots at regug lar intervals therein, an adj aoent movable gate having slots register-able to greater or less degree with the slots in said fixed gate, said movable through a side of the box, a. casing fixed to the side of the box and through the ends of which said shaft passes, a graduated dial at the outer end of said shaft by which said shaft may be rotated to efiect amovement of said movable to, a pointer on the outer end of said casing cooperating with the graduations onsaiddial, a disc fixed to'the shaft between the endslof said casing, and a scale in reading relation tosaid disc.

9. A coating device comprising a box for gate having a slot therein, a roll engaging in said slot, a shaft to the in: her end of which said roll is fixed threaded containing liquid coating material, a fixed gate spaced from the ends of the box and extending from one side of the box to the other,

said gate having a plurality of slots therein,

and ad acent moveable gate having slots registerable to greater or ess degree with the slots in said fixed gate to regulate the flow through the slots on to the bottom of the box beyond said gates, and a stationary gate beyond said first-mentioned ates having obstructing ends and under w ich said coatin material flows in a layer of predetermine width.

10. A coating device comprising a box for containing liquid coating material, a fixed gate spaced 'fromrthe ends of the box and extending from'one side of the box to the other, said gate having a plurality of slots therein, an adjacent movable gate having slots registerable to greater or less degree with the slots in said fixed gate to regulate the flow through said gates on to the bottom of the box beyond said gates, a stationary gate beyond said first-mentioned gates, having a slot formed inwardly of each of its ends, and material wrap ed over the bottdm edge of said ate and t rough said slots and resting on the ottom of the box to prevent a fiow of material thereunder, the lower edge of said slotted gate between the obstructed ends smoothing out any marked unevenness in the coating material as it flows in a layer thereunder.

11. The combination with arotary roll over which a continuous sheet passes at predetermined rate, of a coating device comprising a box having an outlet at its bottom, means for continuously forming a thin layer of coating material of substantially uniform, predetermined thickness on the bottom of the ox and discharging it by gravity through said outlet on to said sheet while supported on said roll, a doctor at said opening adjustable toward and from said roll to distribute the material evenly on said sheet, and a pair of obstructions wi ing on the surface of said roll at the ends 0 said outlet to revent the material from flowing laterally 0 said open- 12. The combination with a roll over which a continuous sheet asses at predetermined rate, of a coating evice comprising a box having an outlet, means for continuously forminga thin layer of coating material of substantially uniform, predetermined thickness discharging by gravity through said outlet on to said sheet, a doctor for distributin the material evenly on said sheet, a pair 0 shafts threaded in said doctor, and means for rotatin saidshafts independently or simultaneous y to effect a raising or lowering of the doctor at either or both ends.

13; The combination with a roll over which a continuous sheet asses at predetermined rate, of a coating evice comprisin a box having, an outlet, means for continuously" forming a thin layer of coating material of substantially uniform, predetermined thick ness dischargin by gravity through said out- "let on to said s eet while supported on said roll, a knife-edged doctor for distributing the material evenl on said sheet, a pair of shafts threaded in said doctor, a worm gear loosely mounted on each shaft, a knob resting on said gear and fixed to the shaft, means for clamping said knob to said gear, a shaft provided with worms meshing with said gears, and means for rotating said shaft.

14. The combination with a roll over which a continuous sheet asses at predetermined rate, of a coating evice comprisin a box having an outlet, :1 member on which said box is hingedly supported and riding on said roll, and means for continuously forming a thin layer of coating material of substantially uniform, predetermined thickness dischar iplg by gravity through said outlet on to said s set.

15. The combination with a roll over which a continuous sheet passes at predetermined rate, of a coating device comprising a box having an outlet, a member on which said box is hin edly supported, means for continuously arming a layer of coating material of substantially uniform, predetermined thickness discharging by gravity through said outlet on to said sheet, a pair of rollers on which said box is supported on said roll, a shaft extending from one side of the box to the other, on which said rollers are journaled, a pair of lever arms pivotally secured to the sides of said box and to which said shaft is fixed, and means for adjusting said box relative to said lever arms, thereby to adjust said outlet relative to said sheet.

16. The combination with a roll over which a continuous sheet passes at predetermined rate, of a coatingdevice comprising a box having an outlet, a member on which said box is hin edly supported, means for continuousl forming a layer of coating material of pre etermined thickness gravity through said outlet on to said sheet, a pair of rollers on which said box is sup- --ported on said roll, a shaft extending from one side of the box to the other and on which said rollers are journaled, a pair of lever arms pivotall secured to the sides of said box and to which said shaft is fixed, lugs projecting from each side of the box above the corresponding lever arm, and an adjusting screw threaded through each lu and bearing against each arm to permit t e box' to be raised or lowered relative to each or both arms.

17. Apparatus of the class described, com

discharging by e prising a device for containing liquid material, a material supply tube on which said device is hingedly supported, a tank for containing material above said device and com- 'municating with saidtube at one end, and a in said one lower tank.

tank =for containing material below saidde vice and communicating with said tube at its other end, the interior of said device communicating only with said first-mentioned tank while in one position and with said second-mentioned tank while in another position.

18. Apparatus of the class described, comprising a device for containing liquid material, a material supply tube on'which said device is hingedly supported, a tank for containing material above said device and communicating with said tube at one end, a tank for containing material below said device and communicating with said tube at the other end, the interior of said device communicating with said first-mentioned tank only while in one position and with said second-mentioned tank only while in another position, and means for maintaining a constant head of material in said device while it is in said one position.

19. Apparatus of the class described, comprising a device for containing liquid material, a material supply tube on which said device is hingedly supported, a tank for containing material above said device and communicating with said tube at one end, a tank for containing material below said device and communicating with said tube at the other end, the interior of said device communicating only with said first-mentioned tank while in one position and with said second-mentioned tank while in another position, and an overflow pipe for maintaining a constant head of material in said device when in said one position and discharging into said lower tank.

20. Apparatus of the class described, comprising a closed box for containin a liquid coating material comprising a v0 atile solvent, said box having an outlet at its bottom, a vent pipe to maintain atmospheric pressure within said box, a material supply tube on which said device is hingedly supported, a tank for containing material below said device and communicating with said tube at the other end, the interior of said device communicating only with said first-mentioned tank while in one position and with said secfor maintaining a constant head of material in said device when position and discharging into said ing from said manifold into said upper tank,

and means for passin material from said lower tank through said manifold and-pipes into said upper tank, the interior of said device communicating with said upper tank only while in one position and with said lower tank only while in another position.

22. Apparatus of the class described, comprising a device for containing liquid material, a material supply tube on which said device is hingedly supported, a tank for containing material above said device and communicating with said tube at one end, a closed tank for containing material below said device and communicating with said tube at the other end, the interior of said device communicating with said upper tank only while in one position and with said lower tank only while in another position, pipes leading from said lower tank into said upper tank, and means for forcing the material through said pipes into said upper tank.

23. Apparatus of the class described, comprising a device for containing liquid material, a supply tube on which said device is hingedly supported, a tank for containing material above said device and communicating with said tube at one end, a tank below said device and communicating with said tube at the other end, the interior of said device communicatin with said first-mentioned tank only while in one position and with said second-mentioned tank only while in another position, and means for supplying material from said second-mentioned tank to said first-mentioned tank.

24. Apparatus of the class described, comprising a roll over which a continuous sheet passes, a device riding on said roll for discharging a liquid coating material on said sheet while passing over said roll, a material supply tube on which said device is hingedly supported, a tank for containing material above said device and communicating with said tube atone end, and a tank for containing material below said device and commn nicating with said tube at the other end, the interior of said device communicating with said f rst-mentioned tank while said device is in riding position on said roll and communicatmg wlth said second-mentioned tank wllipn swung out of riding position on said ro Apparatus of the class described, comprising a device for containing liquid material, a material supply tube on which said device is hingedly supported, a plug in said tube having a pair of ports formed through its sides and its opposite ends, each of said ports bein communicable with the interior of said device, a tank for containing material above said device and communicating with said tube at one end, and a tank for containing material below said device and communicating with the tube at its other end, the interior of said device communicating said sheet while through one of said ports with said first mentioned tank only while said device is in one position and communicating through the other of said orts with said second-mentioned tank on y while said device is in another position. x

26. Apparatus of the class described, com prising a device for containing liquid material, a material supply tube on which said device is hingedly supported a plug in said tube havin an inlet port and an outlet port communica is with the interior of the device and formed through the sides and opposite ends of said plug, a tankfor containm liquid material above said device and disc arging by gravity into one end of said tube a tank for containing material below said evice and communicating with said tube at its other end, the interior of said device communicatin' through the inlet port with said upper ta only while said device is in one osition to allow material to flow into said evice, and communicating throu h the outlet port with said lower tank to al 0w the device to be drained onl while said device is in another position, an means for controlling the rate of flow of material into said device.

27. Apparatus of the class described, comprising a roll over which a continuous sheet may pass, a device riding on said roll for discharging a liquid coating material on to said sheet while passing over said roll, a materialsupply tube on which said device is hingedly supported, a pin in said tube havin a pair of ports forme through its an opposite ends, each of said ports being communicable with the interior of said device, a tank for containing material above said device and communicating with said tube at one end, and a tank for containing material below said device and communicating with the tube at its other end, theinterior of said device communicating throiigh one of said ports with said upper tank 0 y while said device is in riding position and communicating through the other of sa d ports with sald lower tank only when said device is swung out of riding position on said roll.

28. Apparatus of the class described, com-,

prising a roll over which a continuous sheet passes, a device riding on said roll for charging a liquid coating material on to assing over said roll, a material supply tube on which sa d device is hingedly supported, a pin in said tube having a pair of ports forme through its sides and opposite ends each of said ports being communicable with the interior of said de vice, a tank for containing material above said device and communicating with said tube at one end, a tank for containing material below said device and communicating with the tube at its other end, the interior of said device communicating through one of said ports with said upper tank while said i device is in riding position only and com municating through the other of said ports with said lower tank whn said device is 5 swung outof riding position on said roll, and means for feeding material from said lower tank into said up er tank.

In testimony w ereof I have aflixed my signature.

w AZARIAH Y. PEARL.

swung out of riding position on said roll, and

means for feeding material from said lower tank into said up er tank.

In testimony w ereof I have aifixed my signature.

- AZARIAH Y. PEARL.

canmlcara 0F CORRECTION.

Patent No. 1,829,153. Granted 0mm 27, 1931, to

AZARIAH Y. PEARL.

It is hereby certified that the assignee iii the above numbered patent was erroneously described and specified as "Laboratories Sevigne Pearl, of Windsor, Vermont. a corporation of Vermont", whereas said assignee should have been described and specified as Laboratoires Sevigne-Pearl, Inc., of Windsor, Vermont, a corporation of Vermont, as shown by the records of assignments in this office; and-that the said Letters Patent should be read with this correc'tion therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 22nd day of December, A. D. 1931.

M. J. Moore,

(Seal) Acting Commissioner of Patents.

CERTIFICATE or CORRECTION.

Patent No. l,829,l53. Granted October 27. 1931. to

AZARIAH r. PEARL.

- it is hereby certified that the assignee iii the above numbered patent was erroneously described and specified as "Laboratories Sevigne Pearl, of Windsor. Vermont, a corporation of Vermont", whereas said assignee should have been described and specified as Laboratoirea Sevigne-Pearl, Inc., of Windsor. Vermont, a corporation of Vermont, as shown by the records of assignments in this office; and that the said Letters Patent should be read with this eorrec'tiou therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 22nd day of December, A. D 1931.

a J. Moore. (Seal) Acting Commissioner oi Patents. 

